Aspiration pneumonia
| Classification according to ICD-10 | |
|---|---|
| J69 | Pneumonia caused by aspiration of solid or liquid substances |
| J69.0 | Pneumonia from food, milk, or vomit |
| J69.1 | Pneumonia caused by oils and extracts (lipid pneumonia) |
| J69.8 | Pneumonia caused by aspiration of other solid or liquid substances (e.g. blood) |
| P24.9 | Newborn aspiration syndrome , unspecified Neonatal aspiration pneumonia on A. |
| J95.4 | Mendelson's syndrome |
| ICD-10 online (WHO version 2019) | |
The aspiration pneumonia (derived from " aspiration ") is a pulmonary inflammation that arises because Regurgitated or back flowed reach stomach contents or other substances into the lungs and by their specific properties inflammatory responses cause.
Aspiration pneumonia occurs e.g. B. often in the context of cardiopulmonary resuscitation , in shock , in unconsciousness , in swallowing paralysis due to neurological failures or diseases of the central nervous system, disorders of the esophageal function with increased reflux and in chronic alcoholism. Aspiration pneumonia can also include an infection of the lungs with various bacterial pathogens (such as Peptostreptococcus species).
physiology
During the normal swallowing process, the nasopharynx is closed by the soft palate and the larynx is closed by the epiglottis so that the food cannot get into the airways. Since breathing is interrupted at the moment of swallowing, the swallowing process and epiglottis closure must be well timed in order not to interrupt the oxygen supply for too long. If swallowing occurs nevertheless, a violent cough reflex ensures that the food pulp containing bacteria does not remain in the airways. Even under normal conditions, small amounts of nasopharyngeal secretions are aspirated during sleep. Some authors suggest that this microaspiration is a common mechanism in the development of pneumonia.
Pathogenesis and Risk Factors
The risk of aspiration pneumonia is increased by the following factors:
- Difficulty swallowing
- Impaired consciousness
- increased risk of aspirating stomach contents
- decreased cough reflex
The swallowing process can be impaired by:
- Esophageal diseases: esophageal carcinoma , stricture (narrowing)
- COPD
- neurological diseases: epileptic seizures , multiple sclerosis , Parkinson's disease , stroke , dementia
- Ventilation: Extubation is particularly critical
- Impaired closure of the epiglottis: after therapy for larynx and hypopharyngeal carcinomas .
Consciousness can be clouded by:
- acute stroke
- Cardiac arrest , resuscitation
- drug overdose: opiates , psychotropic drugs
- anesthesia
- Alcohol excess
The risk of aspirating stomach contents is increased with:
- Reflux
- Tube feeding
- Induction of anesthesia without food abstinence
The cough reflex can be decreased by:
- Medication
- alcohol
- stroke
- Dementia,
- degenerative neurological diseases
- Clouding of consciousness
Another cause is an esophago-tracheal fistula , which can arise after carcinoma of the esophagus, the trachea or the main bronchi.
clinic
Since aspiration pneumonia has a wide spectrum of aspirated fluid, aspiration amount, germ content of the aspirate, comorbidity of the patient and affected section of the lungs and bronchial tree, the clinical presentation is also variable. In any case, a prerequisite is macro aspiration, although the exact amount of aspirate required is unclear. The initial symptoms range from asymptomatic to life-threatening respiratory failure. Contact of the aspirate with the bronchi can cause bronchospasm, an asthma attack or a persistent cough. The changes in the lung parenchyma typically only appear after a few hours or days. Pneumonia after aspiration is difficult to distinguish from any other bacterial infection. In elderly patients, pneumonia mortality is higher after aspiration than without aspiration. This increased mortality was also found in community-acquired pneumonia. Diagnostic imaging (chest x-ray, chest CT) shows infiltrates in the lower sections of the lungs. In the supine position, the basal segments of the lower lobe are affected. When held upright, the upper lower lobe segments or the posterior upper lobe segments are most often infiltrated. A normal x-ray shows no signs of aspiration in up to 60%. The diagnosis of aspiration is better on CT . HRCT (CT with high resolution) has the highest diagnostic accuracy.
Mendelson's syndrome
Under the Mendelson's syndrome means a aspiration by the aspiration caused by acid contents of the stomach in anesthetized patients. In contrast to the other aspiration pneumonia, it is listed in the ICD under damage “after medical measures”. In about 50% of cases of aspiration, aspiration of the stomach contents leads to pneumonia . For this, the pH value must be <2.5 and the aspiration volume must be more than 0.4 ml / kg body weight. Originally, Mendelson's syndrome occurred primarily during delivery under general anesthesia . The stomach acid causes alveolitis . It can bronchospasm , atelectasis , shock and ARDS come. With modern anesthesia, Mendelson's syndrome occurs in only one of 3216 anesthetics, most often in emergencies in which food abstinence cannot be observed (1: 895).
The mortality of Mendelson's syndrome is between 20 and 50% depending on the clinic.
Individual evidence
- ^ Marianne Abele-Horn: Antimicrobial Therapy. Decision support for the treatment and prophylaxis of infectious diseases. With the collaboration of Werner Heinz, Hartwig Klinker, Johann Schurz and August Stich, 2nd, revised and expanded edition. Peter Wiehl, Marburg 2009, ISBN 978-3-927219-14-4 , pp. 91 and 265.
- ^ A b Lionel A Mandell, Michael S Niederman: Aspiration Pneumonia . In: New England Journal of Medicine . tape 380 , no. 7 , February 14, 2019, ISSN 0028-4793 , p. 651-663 , doi : 10.1056 / NEJMra1714562 ( nejm.org [accessed March 9, 2019]).
- ↑ K. Gleeson, DF Eggli, SL Maxwell: Quantitative aspiration during sleep in normal subjects . In: Chest . tape 111 , no. 5 , May 1997, ISSN 0012-3692 , pp. 1266-1272 , PMID 9149581 .
- ↑ David M. DiBardino, Richard G. Wunderink: aspiration pneumonia: a review of modern trends . In: Journal of Critical Care . tape 30 , no. 1 , February 2015, ISSN 1557-8615 , p. 40-48 , doi : 10.1016 / j.jcrc.2014.07.011 , PMID 25129577 .
- ↑ Héctor Pinargote, Jose Manuel Ramos, Alina Zurita, Joaquin Portilla: Clinical features and outcomes of aspiration pneumonia and non-aspiration pneumonia in octogenarians and nonagenarians admitted in a General Internal Medicine Unit . In: Revista Espanola De Quimioterapia: Publicacion Oficial De La Sociedad Espanola De Quimioterapia . tape 28 , no. 6 , December 2015, ISSN 1988-9518 , p. 310-313 , PMID 26621175 .
- ↑ Naoyuki Miyashita, Yasuhiro Kawai, Takaaki Tanaka, Hiroto Akaike, Hideto Teranishi: Detection failure rate of chest radiography for the identification of nursing and healthcare-associated pneumonia . In: Journal of Infection and Chemotherapy: Official Journal of the Japan Society of Chemotherapy . tape 21 , no. 7 , 2015, ISSN 1437-7780 , p. 492-496 , doi : 10.1016 / j.jiac.2015.03.002 , PMID 25842163 .
- ^ R. Rossaint, C. Werner, B. Zwißler, U. Nollert: The anesthesiology: General and special anesthesiology, pain therapy and intensive medicine. 1st edition. Springer Verlag, 2004, ISBN 3-540-00077-1 .
- ^ MA Warner, ME Warner, JG Weber: Clinical significance of pulmonary aspiration during the perioperative period . In: Anesthesiology . tape 78 , no. 1 , 1993, ISSN 0003-3022 , pp. 56-62 , PMID 8424572 .
